Furnace baffle construction and arrangement



J. E, J. TONER 2,576,053

F'URNACE BAFFLE CONSTRUCTION AND ARRANGEMENT 2 SHEETS-SHEET 1 MCI., i.

Nov. 20, 1951 Filed July 1, 1949 Inventor Nov. 20, 1951 J. E. J. TONER2,576,053

' FURNACE BAFFLE CONSTRUCTION AND ARRANGEMENT Filed July 1, 1949 2sHEETs-SHEET 2 Inl/enfer Y JmeJE. Tone/1,

Patented Nov. 20, 1951 l UNITED STATES FURNACEBAFFLE CONSTRUCTION ANDARRAN GEMEN T James E. J. Toner, Bethlehem, Pa., assignor to BethlehemFoundry and Machine Company, Bethlehem, Pa., a corporation ofPennsylvania Application July 1, 1949, Serial No. 102,518

18 Claims. l

This invention relates to new and useful improvements in furnaces, andmore particularly to furnaces of the general type disclosed in U. S.atent No. 2,264,226 granted November 25', 1941.

lin this type of furnace, air is introduced tangentially into a tubularcombustion chamber and the fuel is supplied to the chamber in an' axialdirection. From the beginning, in domestic size furnaces of this type,the limitations in respect of thelength of the tubular combustionchambers for household installations wereY such that the combustionchambers could not be made long enough for complete combustion ofthefuel to take place within the tubular chambers. The result of this wasthat not only was the furnace ineilcient` in operation but substantial'smoke was present causing carbonization not only on theK walls of thefurnace and stack but also at the fuel nozzle to an extent that thelatter became inoperative after short periods of use.

One solution to the difficulties presented appeared to be the necessityfor intermixing the fuel and air in the tubular combustion chamber to anextent that would insure complete combustion of the fuel within thechamber. In the aforesaid patent this was sought to be accomplished byinserting in the tubular combustion chamber an annular bale memberwhich, while preventing too rapid movement of the burning fuel towardthe outlet end of the chamber, functioned primarily to cause a sudden orabrupt change in the flow of iiuid through the combustion chamber thuscreating a turbulent condition at the bale that produced a satisfactoryintermixing of the fuel and air for combustion. Later, additional baieswere installed as requi-red.

The baffles of the aforesaid` patent furnished an adequate solution tothe problem so long as the domestic fuel oils available consisted mainlyof distillate oils. However, since the end of the war the use ofcatalyst cracked oils in domestic heating fuels has increased until atthe present time the maior proportion of the oils in domestic fuel oilsare produced by catalytic cracking processes. These so-called cat-crackoils have nen` found to have different combustion properties andcharacteristics than distillate oils with the result that the baillestructure of the aforesaid patent did not provide the degree of fuel-airmixture required to effect complete combustion of such cat-crack oilswithin the relatively shcrt tubular combustion chambers of domestic .mefurnaces.

With the foregoing in mind, the principal ob- 2 ject of the presentinvention is to provide for a furnace of the type described a novelbaffle construction which is operable to effect an intermiXing of fueland air to a degree causing cornplete combustion of the fuel to takeplace within the furnace combustion chamber.

Another object of the invention is to provide a novel baffleconstruction as set forth which s operable to cause a sudden and abruptchange in the flow of fluid through a tubular combustion chamber and tocreate a maximum degree of turbulence in the fluid at and through thebaffle to thereby cause maximum intermxture of the fuel and air andinsure complete combustion of the mixture within the chamber.

A further object of the invention is to provide in a furnace of the typeset forth a novel arrangement of baffles embodying the aforesaidfeatures and advantages.

These and other objects of the invention and the various features anddetails of the construction and operation thereof are hereinafter fullyset forth and Ydescribed, with reference to the accompanying drawings,in which:

Figure 1 is a longitudinal sectional view vertically through a furnaceembodying the present invention;

Fig. 2 is a view in perspective of a baffle member constructed accordingto the present invention, a portion thereof being broken away to betterillustrate certain details of the construction;

3 is an enlarged elevational. vieW of the bailie from the outlet endthereof;

Fig. 4 is a sectional. view taken on line 4l, Fig. 3;

Fig. 5 is a fragmentary sectional View of the combustion chamber of afurnace showing a baffle arrangement different from that in Fig. l;`

Fig. 6 is a view similar to Fig. 2 of a modified form of baille;

Fig. '7 is an enlarged elevational View of the baille construction shownin lig. 6, from the outlet end thereof;

Fig. 8 is a sectional View on line Fig. 7; and

Figs. 9 and 10, respectively, are fragmentary sectional views showingother arrangements of baies which give satisfactory results.

Referring now to the drawing, the invention is shown conjunction with adomestic furnace of the type described comprising an open-ended tubularcombustion chamber l and a surrounding series of open-ended fire tubes2. Air is introduced tangentially into the combustion tube l4 by meansof a blower t and the fuel to be burned is discharged coaxially into thechamber I by means of a suitable nozzle 1i having associated therewiththe customary spark ignition 5.

The combustion gases leaving the outlet end of the tubular chamber Imake a return pass through the re tubes 2 and are then discharged up theusual stack 6. The tubular combustion chamber i is lined with aplurality of refractory sleeves i interspersed with battles and 9arranged, for example, as shown in Fig. l of the drawing. The baiile maybe of the type and construction shown and described in the patentpreviously referred to herein.

The present invention is concerned primarily with the construction ofthe baffle 9 and the arrangement of one or more such baliles within thetubular combustion chamber I of the furnace. Referring now moreparticularly to Figs. 2, 3 and 4 of the drawing, the baiiie 9 is of agenerally annular construction and preferably is fabricated ofrefractory material. The baffle has a generally tapered opening Ii)therethrough which diverges in the direction of passage of the air andfuel therethrough. As shown in the drawing, the opening il) through thebaille 9 is of irregular configuration or shape and is provided with aplurality of recesses I I arranged in uniformly spaced relation aboutthe baiiie opening i@ and the contour of the recesses II is such thatthere is formed'between adjacent recesses a rib portion I2 whichprojects inwardly of the baffle toward the center of the opening of thebaffle, the ribs I2 being disposed alternately with said recesses aroundthe baiiie opening IB. Y

As shown in Fig. 4 of the drawing, the surfaces of the recesses II andthe surfaces of the ribs l2 both slope outwardly or diverge in thedirection of fluid flow through the baiiie opening. Furthermore, as willbe apparent from a reference to Fig. 3 of the drawing, the arrangementof the recesses II and ribs I2 as well as the angle of divergence oftheir respective surfaces is'such that the baffle opening li) is ofcorrespondingly irregular contour Aat both the inlet and outlet sidesofthe bafe.

In a tubular combustion chamber, for example, such as shown in Fig. l ofthe drawing, the inlet end face I3 of the baiie S constitutes a barrierwhich effects a sudden change in the direction of ow of the air throughthe chamber and sets up a high degree of turbulence in the air resultingin a substantial initial mixture of the air and fuel which, by reason ofthe pressure of the continuously incoming air supplied to the combustionchamber, is caused to iiow in a generally spiral course through theopening i il in the baiile. As the partially mixed fuel and air thusmoves in a spiral course through the opening of the baille 9, .theirregular surface which is provided by the alternately arranged recessesil and inwardly projecting or raised rib portions i2, creates a veryhigh degree of turbulence in the Huid as it passes through the baiiiethereby causing substantially complete intermixing of the fuel and airand producing a highly combustible mixture which is completely burnedduring the remainder of its passage through the adjacent refractorysleeve 1, baiile 8 and subsequent sleeves 'i prior to reaching theoutlet end of the tubular com bustion chamber. Another arrangement of aplurality of baffles 9 in association with sleeves 'I and a baffle 8 ina, tubular combustion chamber of longer length is shown in Fig. of thedrawing. A modified form of the bafe is shown in Figs. 6, 7 and 8 of thedrawing wherein there is illustrated a baffle member 9a, of generallyannular construction, having a generally tapered opening Illatherethrough which diverges in the direction of passage of the air andfuel through the baiiie and is provided with a plurality of recesses Haarranged in uniformly spaced relation about the baffle opening lila withrespect to the alternately arranged ribs 62a that project inwardly ofthe baille toward the opening there- Y through.

As shown in the drawing, the surfaces of the recesses I Ia and thesurfaces of the ribs I2a both slope outwardly or diverge in thedirection of flow through the baille opening Ita and, in this particularembodiment of the bale construction, the angle of slope or divergence ofthe baifle surfaces surrounding the opening Illa is greater than theangle of slope of the corresponding surfaces of the baiiie constructionpreviously described so that in the construction of Figs. 6, 7 and 8 thesurfaces merge into a truly circular surface surrounding the baffleopening lila at the outlet side of the baflie. Thus, in the form ofbaiiie construction shown in Figs. 6, 7, and 8, the baffle opening Idais of irregular contour at the inlet side only of the baiiie and is oftruly circular contour orshape at the outlet side thereof. The operationof the several recesses ila and ribs i2a in the baiiie construction ofFigs. 6, '7 and 8 to create a high degree of turbulence and intermixtureof air and fuel during passage thereof through the baille opening lilais substantially the same as that set forth with respect to the bailleconstruction shown in Figs. 2, 3 and 4.

Other arrangements of bafes which give satisfactory results are shown inFigs. 9 and 10 of the drawings, Fig. 9 showing a modified arrangement ofthe baiile assembly of Fig. 1 and Fig. 10 showing a modification of thebaflie assembly of Fig. 5. In the case of Figs. 9 and 10 the baiearrangements are similar, respectively, toY those shown in Figs. 1 and 5of the drawings except there has been added intermediate the firstbaiile 9 or 9a and the sleeve 'i or "la, as the case may be, a baiiieIii or Ida, respectively, having a tapered internal opening of circularconguration with the larger end of said opening facing the inlet end ofthe combustion tube so that the smaller end of the opening is disposedcontiguous to the inlet end of the opening Il) or lita in theirregularly contoured bailies 9 orV 9a, respectively. The use of abaffle I6 or lli-a constructed and arranged as described provides withthe adjacent baiile of irregular contour a restriction in the combustionchambers which functions in the manner of a nozzle or venturi to provideincreased turbulence and more complete intermixing of the air and fuelpassing therethrough.

From the foregoing description it will be observed that the presentinvention provides a novel bafiie construction for furnaces of the typedescribed which embodies novel features of construction and arrangementoperable to effect a maximum intermixing of fuel and air to the degreerequired to effect complete combustion Vof so-called cat-crack oilswithin the tubular combustion chamber of the furnace. The invention alsoprovides a novel baffle construction as set forth which in addition Vtoeffecting a sudden or abrupt change in the direction of flow through thecombustion chamber operates effectively to create a high degree ofturbulence in the fluid as the latter passes through the baffle therebyto effect optimum intermixture of the fuel and air and insure completecombustion thereof within ammessa 5;. the-limitsioifthei combustion;tube of, the; furnaces,l

While: certain embodimentsrotthe present ini--` vention have: beenillustrated andfdeseribedrfhereein=, itisanotz-intended to;limittheinventiorr tosucn disclosures, and changes and-,imodificationsimay bei made:` therein and;theretofwitbinfthe scope` of; the;yfollowingl i. claims.

I claim:

1r.. As: an' article; otxmanufacture'.. a. baille' compris-ing: agenerally annular` member having a, taperedfiinternali` opening;therethrough oifirregu lar :configuration defined; by,ialternately,`disposed recesses rand: ribszextending. axially of;the:member,1 andiarranged in, uniformly spaced; relation arounid` said opening.saidireoessea .being tapered intthef direction: oftap'erkv of the;opening. through. the? member andisaidfiribs being `tapered' in the`oppositef direction.

2; As:amarti'cle` of manufacture; a. baille comfprising:` argenerally.-` annular member having a; tapered; internal; opeuingfvtherethrough of irregultu'iconilguration` defined byvalternately`disposed recesseseandribs extending.:axiallyofthe member andl arrangedin.. uniformly spacedl` relation., around said opening; the. surfaces ofsaidrecessesf and' ribs sloping entirely throughY the bailieopening at apredetermined anglefto-causefsaid openingf to be of'correspondingirregular contour at both* endsV thereof.

3'. les` an .article oft manufacture, a. baille comprisingV a generallyannular member having a: tapered'internalopening` therethrough ofirregular conligurationr denedlby i alternatelyadisposed iroundedrecesses, and inwardly projected" ribs` extending axiallyof"thehmemberI and arranged" inwuniformly spaced relation `aroundsaidopenl ing, said recesses! beingtaperediin; the direction oftaper of the:opening through` they member and said` ribs. b'eingftaperedfin. the:opposite directions.

4.' As.- an: article-ofrnanui'acture, a bailleconfi-v prising agenerally annular member havingv a tapered internal? openingtherethrough of irregulariconn'guration delnedby alternately disposed?:recesses-.andfribs.` extending axially `of the member@V and:arranged-1" in uniformly spaced relation, aroundisaid; opening,.thesurfaces ot'V said. recesses. andfribssrsloping .entirelyy through:`the baille openingvatza predetermined` angl'eto,` causesaid openingtoV`be; of correspondingly irregularv contour at bothi ends thereof;sai'derecesses being taperedin4` the direction .ot tapersof; the openingthrough,` the: member'. and@ said z ribs beingV tapereda` the op positedirection..

5. Asv anar-ticle o-f;.man11f acture,. a baille com,- p risingf` agenerally annular;V member having a taperedf-` internal" openingtherethrough of ir-`` regular; configuration, donned: byr alternatelydis.- posed recessesrand` ribs` arranged in uniformly' spaced relationaround said opening, the surfaces; ofsaidrecessea and ribs sloping,-im-one direction through the-i baille at: a `predetermined;` angle to4cause saidsurfaces-r, to merge. intona, circular sure face adjacentoneendet theopening anclfthereby` provide a; batiefopeningfof,reglulancontourrat, said. one,endthe other end of; the baliieopening,hav ing an` .irregular contour.

6. As,l an article. ot manufacture, a-bailiecomf-V prising a: generallyannular member having a1 tapered internalr opening therethrough-ofirreg` ular coniiguration donned by alternately disposed: roundedrecesses and` inwardly projected ribs arranged,inuniormly spacedrelation aroundsa-id` opening, `the surfaces off said recesses andribs'V sloping intona direction through the: baille `at `apredetermined-I angle te* cause` saidsurfaces: to-

mergeinto a. circular surface adjacent one-endu of thefopeningf andthereby provide a,bailleopelby ing ofV- regularcontourat said one end;the-other end of; the baille opening having an` irregular contour.

'7. In a furnacecomprising a. cylindrical" com-H bustionr tube totheinletvend of. which air is supplied; tangentially and fluid fueluisintroduced` axially thereof, at least one: baule nsaid tube inwardlyadjacent the inletend of the tube hav.- inga tapered internal opening ofirregular con-- iiguratiow constituted of alternately arranged recessesand ribs with the smaller end of said4 opening disposed adjacent saidinlet end of. the, tube, atleast one: sleeve 'sectionrlining the tube,

atv the other end of said baille, and another baille inA thetubefat theother side ot said. sleevefrom,

the first mentionedA baille and having :a tapered internal opening ofcircular configuration with` the smaller end thereofl disposed adjacentsaid sleeve.

8.- n a furnace comprising a cylindrical com-- bustion tube to the inletend of which air is supplied tangentially and fluid iuelis introduced`,axially thereof, at least one baille in said. tube inwardlyadjaeentthelinlet end of the tube having a tapered internal openingr ofirregular configuration constituted of alternately arranged` ;there of,a sleeve-sectionliningthe tube at the other end-oi` said baille, andanother baille in the tube at the other sideof said sleeve from the rstmentioned baille andihaving a `tapered,

internal openingof circular configuration with the smaller end thereof`disposed adjacent said sleeve.

9i; In a` furnace comprising a cylindrical combustion tube to.- theinlet end of which air is` supplied tangentiallyand fluid fuel isYintroduced axially thereot,` at least' oney baille i-n said tubeinwardly adjacent` the tube. inlet` endhaving a tapered internalopeningof irregular conguration constituted` of'a-lternately arrangedrecesses and ribs with; the smaller end of said openingdisposedzadjacentthe inletendof the' tube, the surfaces of said recesses and ribslsloping throught the bailleat` a predetermined angle to cause saidsurfacesy tomerge into-a circularsura face adjacent the larger end` of`thev opening and thereby provide a baille opening` of'` regular oontourat said larger ende with the smaller end of the baille opening having anirregular contour, and another baille .in the tube spacedulon-`gitudinally. thereof fromithe rst baille and havting; a.. tapered,inter-nal openingot circular con-- figuration with the smaller endthereof dis-I posed adjacent said ilrst baille.

10. In` a. furnace comprising. acylindrical combustion tube tothe inletend. of which air is` sup,m

plied tangentially and uidfuel: is introduced.

axially thereof, a `sleeve section lining the inlet end-portionof thecombustion tube, a` pair oi bailles in juxtapositionvin said tubeinwardly adjacent .the sleeve section eachfher/ingA a; tapered internalopeningl of irreefuleu' configuration- 1 con` stituted` of alternatelyarranged recessesand ribs, with the: smaller end' ofthe opening: diseposed adjacent the inlet end of: tlietube; a plu.- rality` oiA sleeve`sections lining the tube at.` the otherf of saidrpair oixbaiiles,lanother baille in the tube adjacent said plurality of 'sleeves' havinga tapered internal opening of circular configuration with the smallerend thereof facing the inlet end of the tube, and a plurality ofadditional sleeve sections lining said tube at the other end of saidother baiile.

1l. In a furnace comprising a cylindrical combustion tube to the inletend of which air is supplied tangentially and fluid fuel is introducedaxially thereof, a pair of baffles in said tube inwardly adjacent theinlet end thereof each having a tapered internal opening of irregularconfiguration constituted of alternately arranged recesses and ribs withthe smaller end of the opening disposed adjacent the inlet end of thetube, the surfaces of said recesses and ribsV sloping entirely throughthe bale at a predetermined angle to cause the opening to be ofcorrespondingly irregular contour at both ends thereof, a plurality ofsleeve sections lining the tube at the other end of said pair ofbaffles, and another baie in the tube adjacent said sleeves and having atapered internal opening of circular conguration with the smaller endthereof facing said pair of baflies.

12. In a furnace comprising a cylindrical combustion tube to the inletend of which air is supplied tangentially and fluid fuel is introducedaxially'thereof, a sleeve section lining the inlet end portion of thecombustion tube, a pair of baliies in said tube inwardly adjacent thesleeve section each having a tapered internal opening of irregularconfiguration constituted of alternately arranged recesses and ribs withthe smaller end of the opening disposed adjacent the inlet end of thetube, the surfaces of said recesses and ribs sloping through the baiileat a predetermined angle to cause said surfaces to merge into a circularsurface adjacent the larger end of the opening and thereby provide abaiiie opening of regular contour at said larger end with the smallerend of the baffle opening having an irregular contour, a plurality ofsleeve sections lining the tube at the other end of said pair ofbaffles, another baiile in the tube adjacent the last-mentioned sleeveshaving a tapered internal opening of circular configuration With thesmaller end thereof facing the inlet end of the tube, and a plurality ofadditional sleeve sections lining said tube at the other end of saidother baille.

13. In a furnace comprising a cylindrical combustion tube to the inletend of which air is supplied tangentially and fluid fuel is introducedaxially thereof, a sleeve section lining the inlet end portion of thecombustion tube, a first baflie in the tube adjacent the sleeve andhaving a tapered internal opening of circular configuration with thelarger end thereof adjacent said sleeve, and a second baifle in saidtube inwardly adjacent the first baffle and having a tapered internalopening of irregular conguration constituted of alternately arrangedrecesses and ribs with the smaller end of said opening disposed adjacentsaid first baiile.

14. In a furnace comprising a cylindrical combustion tube to the inletend of which air is supplied tangentially and fluid fuel is introducedaxially thereof, a sleeve section lining the inlet end portion of thecombustion tube, a first baffle in the tube adjacent the sleeve andhaving a tapered internal opening of circular configuration with thelarger end thereof adjacent said sleeve, a second baffle in said tubeinwardly adjacent the rst baffle and having a tapered internal openingof irregular configuration con? stituted of alternately arrangedrecesses and ribs with' the smaller end of said opening disposedadjacent said rst baie, the surfaces of said recesses and ribs slopingthrough the baflie 'at a predetermined angle to cause the opening to beof correspondingly irregular contour at both ends thereof.

15. In a furnace comprising a cylindrical combustion tube to the inletend of which air is sup plied tangentially and fluid fuel is introducedaxially thereof, a sleeve section lining the inlet end portion of thecombustion tube, a first bailleV in the tube adjacent the sleeve andhaving a tapered internal opening of circular conguration with thelarger end thereof adjacent said sleeve, a second baie in'said tubeinwardly adjacent the first baille and having a 'tapered internalopening of irregular configuration constituted of alternately arrangedrecesses and ribs with the smaller end of said opening disposed adjacentsaid first bale, a sleeve lining the tube at the other end of saidsecond baffle, and another b ailie in the tube adjacent thelast-mentioned sleeve having a tapered internal opening of circularconfiguration with the smaller end thereof disposed adjacent saidsleeve.

16. In a furnace comprising a cylindrical com-` bustion tube to theinlet end of which air is supplied tangentially and iiuid fuel isintroduced axially thereof, a sleeve section lining the inlet endportion of the combustion tube, a first baffle in the tube adjacent thesleeve and having a tapered internal opening of circular configurationwith the larger end thereof adjacent said sleeve, and a pair of bafflesin said tube inwardly adjacent the first baiile each having a taperedinternal opening of irregular configuration constituted of alternatelyarranged recesses and ribs with the smaller end of said opening disposedadjacent said first baiile.

17. In a furnace comprising a cylindrical cornbustion tube to theinlet'end of which air is supplied tangentially and iiuid fuel isintroducedY axially thereof, a sleeve section lining the inlet endportion of the combustion tube, a first bale in the tube adjacent thesleeve and having a tapered internal opening of circular configurationwith the larger end thereof adjacent said sleeve, and apair of bafflesin said tube inwardly adjacent the first baffle each having a taperedinternal opening of irregular configuration constituted of alternatelyarranged recesses and ribs with the smaller end of said opening disposedadjacent first bafe, the surfaces of said recesses and ribs slopingthrough the baliie at a predetermined angle to cause the opening to beof cor` respondingly irregular contour at both ends thereof.

18. In a furnace comprising a cylindrical combustion tube to the inletend of whichair is supplied tangentially and fluid fuel isV introducedaxially thereof, a sleeve section lining the inlet end portion of thecombustion tube, a first bailie in the tube adjacent the sleeve andhaving a tapered internal opening of circular configuration with thelarger end thereof adjacent said sleeve, and a pair of baffles in saidtube inwardly adjacent the first baiiie each having a tapered internalopening of irregular configuration consttuted of alternately arrangedrecesses and ribs with the smaller end of said opening disposed adjacentsaid first baffle, the surfaces of said recesses and ribs slopingthrough the baiile at a predetermined angle to cause the opening to be 9of correspondingly irregular contour at both ends thereof, sleevesections lining the tube at the other end of said pair of baies, andanother bafe in the tube adjacent the last-mentioned sleeves and havinga tapered internal opening of circular configuration With the smallerend thereof disposed adjacent said sleeves.

JAMES E. J. TONER.

REFERENCES CITED Thefollowing references are of record in the file ofthis patent:

Number Number 10 68,354 235,321

10 UNITED STATES PATENTS Name Date Hague Oct. 4, 1887 Whitney Nov. 14,1893 Smallwood Dec. 30, 1913 Toner Nov. 25, 1941 FOREIGN PATENTS CountryDate Germany May 3, 1893 Germany May 31, 1910 Germany Apr. 10, 1923

